In the related art, national publication No. 2007-506230 of the Japanese translated version of the PCT application proposed a negative plate for use in a lead-acid battery which has such a configuration that a plate filled with a negative active material is constructed as its main body, and a coating layer of a carbon mixture is formed on the surface of the negative active material-filled plate, the carbon mixture being prepared formed by mixing at least two kinds of carbon materials selected from a first carbon material such as carbon black having conductive properties and a second carbon material such as activated carbon having capacitive capacitance and/or pseudo capacitive capacitance and a binding agent. Consequently, it is intended that the lead-acid battery thus produced can have an extended life span through the function of capacitors even when rapid charge/discharge operations are repeated under PSOC conditions.